Need code that counts variables from a method in a class generated randomly for each time the program is run

Can I count each time the variable choice is one or each time the variable choice is two then add up the total times each count was generated?
Ross Gerard is: Drinking some coffee
Ross Gerard is: At work
Ross Gerard is: Eating a snack
Ross Gerard is: At work
Ross Gerard is: Playing with the dogs
Ross Gerard is: Primping in the mirror
Ross Gerard is: Doing Jiu-Jitsu
Ross Gerard is: Playing with the dogs
Ross Gerard is: Eating a snack
Ross Gerard is: Walking
Ross Gerard is: Eating a snack
Ross Gerard is: Playing nintendo
Ross Gerard is: Playing with the dogs
Ross Gerard is: Singing
Ross Gerard is: Walking
Ross Gerard is: Kissing his girlfriend
Ross Gerard is: At work
Ross Gerard is: Swimming
Ross Gerard is: Playing nintendo
Ross Gerard is: Studying Java

import java.util.Random;
class student 
{
 public void studentIsDoing()
{
    for (int counter = 0; counter < 20; counter++)
    {
    Random r = new Random();

    int choice = 1 + r.nextInt(15);
    String response = "";

    if ( choice == 1 )
        response = "Playing with a ball";
    else if ( choice == 2 )
        response = "Studying Java";
    else if ( choice == 3 )
        response = "Kissing his girlfriend";
    else if ( choice == 4 )
        response = "Swimming";
    else if ( choice == 5 )
        response = "Doing Jiu-Jitsu";
    else if ( choice == 6 )
        response = "Reading a paper";
    else if ( choice == 7 )
        response = "Singing";
    else if ( choice == 8 )
        response = "Primping in the mirror";
    else if ( choice == 9 )
        response = "Taking a Shower";
    else if ( choice == 10 )
        response = "Eating a snack";
    else if ( choice == 11 )
        response = "Drinking some coffee";
    else if ( choice == 12 )
        response = "Walking";
    else if ( choice == 13 )
        response = "Playing with the dogs";
    else if ( choice == 14 )
        response = "At work";
    else if ( choice == 15 )
        response = "Playing nintendo";
    else 
        response = "In the Bathroom";

     System.out.println( "Ross Gerard is: " + response );

    }         

}  
}